JP2016114345A - Air conditioner - Google Patents

Abstract

An air conditioner that can blow out warm air at a predetermined temperature in a short time when the heating start time is reached. An air conditioner according to an embodiment includes a refrigeration cycle, temperature detection means for detecting the temperature of the refrigeration cycle, and control means for controlling the refrigeration cycle based on the temperature detected by the temperature detection means, In the preheating operation for driving the refrigeration cycle before the heating start time set by the user, the control means sets an operation frequency range defined by a predetermined upper limit frequency and lower limit frequency for the operation frequency of the compressor. An operation temperature range defined by a predetermined upper limit temperature and lower limit temperature is set with respect to the temperature of the refrigeration cycle, and during the preheating operation, the operation of the refrigeration cycle is specified while continuing the operation of the compressor. The operating frequency of the compressor is changed within a specified operating frequency range so as to be within the temperature range. [Selection] Figure 3

Description

  Embodiments described herein relate generally to an air conditioner.

  Conventionally, by performing a preheating operation for driving the refrigeration cycle before the heating start time set by the user, it is shorter than when starting the normal heating operation at the heating start time. There is an air conditioner that performs a rapid heating operation that can blow warm air of a predetermined temperature into the room (for example, see Patent Document 1).

Japanese Patent No. 5448390

  However, in the past, since the operation of the compressor (compressor) was turned on / off during the preheating operation, if the compressor operation was just turned off at the heating start time, the operation of the compressor was resumed. Had to spend some time. As a result, there is a possibility that the time from when the heating start time is reached until the warm air of a predetermined temperature is blown out may increase.

  Therefore, the embodiment provides an air conditioner that can blow out warm air at a predetermined temperature in a short time when the heating start time comes.

  The air conditioner of the embodiment includes a refrigeration cycle, temperature detection means for detecting the temperature of the refrigeration cycle, and control means for controlling the refrigeration cycle based on the temperature detected by the temperature detection means. In preheating operation in which the refrigeration cycle is driven before the heating start time set by the user, an operating frequency range defined by a predetermined upper limit frequency and lower limit frequency is set for the operating frequency of the compressor and the temperature of the refrigeration cycle An operating temperature range defined by a predetermined upper limit temperature and a lower limit temperature is set for the engine, and during the preheating operation, the compressor operation is continued while the refrigeration cycle temperature is within the specified operating temperature range. Thus, the operating frequency of the compressor is changed within a specified operating frequency range.

The figure which shows the structure of the air conditioner of 1st Embodiment typically. The figure which shows typically the external appearance of the heat storage unit provided in an air conditioner A diagram schematically showing the flow of preheating operation processing by an air conditioner Diagram showing the flow of compressor frequency processing by the air conditioner Fig. 1 schematically showing changes in the refrigeration cycle temperature and compressor operating frequency during preheating operation Figure 2 schematically showing changes in refrigeration cycle temperature and compressor operating frequency during preheating operation The figure which shows typically the change of the temperature of the refrigerating cycle at the time of the preheating driving | operation in 2nd Embodiment, and the operating frequency of a compressor. Diagram showing the flow of compressor frequency processing

Hereinafter, a plurality of embodiments will be described with reference to the drawings. In addition, the same code | symbol is attached | subjected to the site | part substantially common in each embodiment, and the detailed description is abbreviate | omitted.
(First embodiment)
Hereinafter, the first embodiment will be described with reference to FIGS. 1 to 6.

  As shown in FIG. 1, an air conditioner 1 of the present embodiment connects an outdoor unit 2 provided outside, an indoor unit 3 provided indoors, and the outdoor unit 2 and the indoor unit 3. The piping part 4 etc. in which a refrigerant | coolant flows are provided. In the air conditioner 1, switching of operation states such as cooling operation, heating operation, air blowing operation, dehumidifying operation, operation start time reservation setting, and the like are performed by operating means such as a remote controller 5 used by a user. In addition, the air conditioner 1, in association with the present embodiment, can rapidly heat hot air at a predetermined temperature in the room in a shorter time than when a normal heating operation is started when the heating operation is started. Switching between execution and non-operation is set from the remote controller 5.

  The outdoor unit 2 includes a compressor 6, an outdoor heat exchanger 7 (corresponding to an evaporator during heating operation), a decompressor 8, a four-way valve 9, an outdoor temperature sensor 10, an accumulator 11, a heat storage unit 12, an outdoor fan 13, and The outdoor control part 14 (equivalent to a control means) etc. are provided. Although detailed description is omitted, as is well known, the air conditioner 1 switches the refrigerant flow between the cooling operation and the heating operation (in the direction indicated by the arrow A in FIG. 1) by the four-way valve 9, So-called air conditioning control such as cooling operation and heating operation is performed by changing the operation frequency of the compressor 6 or the like.

  The heat storage unit 12 provided in the compressor 6 is composed of a latent heat storage material such as sodium sulfate decahydrate, sodium acetate trihydrate, paraffin or the like. As shown in FIG. 2, the heat storage unit 12 is disposed around the compressor 6 and accumulates heat (hereinafter referred to as exhaust heat) that the compressor 6 discharges during operation. The latent heat storage material has a so-called supercooling characteristic that maintains a liquid state without solidifying even at a temperature below the melting point. When an external shock is applied to the supercooled heat storage unit 12 that has accumulated exhaust heat, The heat storage unit 12 starts to dissipate heat while solidifying.

  As shown in FIG. 1, the indoor unit 3 includes an indoor heat exchanger 15 (corresponding to a condenser during heating operation), an indoor temperature sensor 16 (corresponding to temperature detecting means), and an indoor control unit that controls these. 17 or the like. Although illustration is omitted, a known blower fan is also provided in the vicinity of the indoor heat exchanger 15.

The compressor 6, the outdoor heat exchanger 7, the decompressor 8, the four-way valve 9, the accumulator 11, the indoor heat exchanger 15 and the like constitute a heat pump type refrigeration cycle 18.
Next, the operation of the air conditioner 1 having the above configuration will be described.

  First, the rapid heating operation will be described. In the rapid heating operation, the startup time (the time from the start of the heating operation until the warm air of a predetermined temperature can be blown into the room) is shorter than that in the case of starting the normal heating operation as described above, for example, 1 It is an operational state that can be done in about minutes.

  The rapid heating operation is started in a state where the rapid heating operation mode is set, by the user starting the heating operation by remote control operation, or the heating operation is started in advance according to the user's wake-up time. Time is set by a reserved timer. At this time, if the rapid heating operation mode is not set, or if it is not the set time zone of the rapid heating operation mode, if the operation of the compressor 6 is completely stopped, the refrigeration is attempted even if the heating operation is started. Since the temperature of the cycle 18, especially the temperature of the indoor heat exchanger 15 is low and about room temperature, hot air cannot be blown out immediately.

  Therefore, when the rapid heating operation mode is set, the air conditioner 1 performs the preheating operation in which the refrigeration cycle 18 is driven and heated in advance before the start time when the heating operation is started by the timer. carry out. In addition, by setting in advance to perform a preheating operation before wake-up time in the morning or before returning home in the evening or the like, when the user performs a heating operation start operation with the remote controller 5 in advance, Preheating operation can be carried out. In addition, the indoor control unit 17 of the air conditioner 1 learns the daily operation time zone, estimates the heating start time in the morning, and the heating start time when returning home in the evening, and performs a preheating operation in advance. You may make it prepare.

The air conditioner 1 sets a temperature range in advance with respect to the temperature of the refrigeration cycle 18 during the preheating operation so that the temperature of the refrigeration cycle 18 does not rise or fall during the reserved operation. The set temperature range corresponds to the operating temperature range, the upper limit of the operating temperature range corresponds to the upper limit temperature T _CH1 (see FIG. 5), and the lower limit of the operating temperature range corresponds to the lower limit temperature T _CL (see FIG. 5). To do. These upper limit temperature T _CH1 and lower limit temperature T _CL are provided to define an operating temperature range that is an appropriate temperature range of the refrigeration cycle 18 during the preheating operation.

That is, in the case of the present embodiment, the operation temperature range corresponding to the range from the lower limit temperature _TCL to the upper limit temperature _TCH1 is set in advance as a necessary and appropriate range for performing the rapid heating operation. If the temperature of the refrigeration cycle 18 is within the operating temperature range, the rapid heating operation can be started in a desired state, that is, as designed.

  Now, the temperature of the refrigeration cycle 18 varies depending on the operating state of the compressor 6. Specifically, when the operation of the compressor 6 is started, the temperature of the refrigeration cycle 18 increases, and when the operation of the compressor 6 is stopped, the temperature of the refrigeration cycle 18 decreases. For this reason, the temperature of the refrigeration cycle 18 can be adjusted to some extent by turning the operation of the compressor 6 on and off.

  However, if the operation of the compressor 6 is stopped, it takes time to restart the operation of the compressor 6. Further, since the compressor 6 is stopped in order to reduce the temperature of the refrigeration cycle 18, the temperature continues to decrease when the operation of the compressor 6 is stopped, and the time from the stop of the compressor 6 does not elapse for a predetermined time. When the heating operation is performed, there is a possibility that the temperature of the refrigeration cycle 18 has not reached the temperature necessary for blowing out hot air at a predetermined temperature. As a result, the start-up time from when the heating start time is reached until the hot air of a predetermined temperature is blown out may increase, and the user may not be able to obtain the desired heating feeling. There is.

  Therefore, the air conditioner 1 of the present embodiment preheats the compressor 6 to operate at a frequency lower than that of the normal heating operation so that the warm air at a predetermined temperature can be blown out in a short time when the heating start time comes. Do the driving. This preheating operation is started a predetermined time before the heating start time set by the user.

  Specifically, the air conditioner 1 is a predetermined time (for example, time t1; see FIG. 5) before the heating start time (time t0; see FIG. 5) at which the rapid heating operation set by the user is started. Then, preheating operation is started. In this embodiment, the predetermined time is set to 1 hour. During the preheating operation, the outdoor fan 13 and an indoor fan (not shown) are operated at a predetermined rotational speed.

At time t1, the air conditioner 1 executes the preheating operation process shown in FIG. 3 and the compressor frequency process shown in FIG. The operating frequency of the compressor 6 (hereinafter referred to as the operating frequency R) during the preheating operation is a range defined by a predetermined upper limit frequency _RH and a predetermined lower limit frequency _RL (operation) as shown in FIG. (Corresponding to the frequency range). That is, the operating frequency R of the compressor 6 does not fall below the lower limit frequency _RL during the preheating operation.

Air conditioner 1 first temperature of the refrigeration cycle 18 (hereinafter, referred to as the temperature _{T C)} to get (S1). In the present embodiment, as the temperature T _C of the refrigeration cycle 18, and using a temperature of the indoor heat exchanger 15 detected by the indoor temperature sensor 16.

When acquiring the temperature T _C of the refrigeration cycle 18, the air conditioner 1, when determining whether the compressor 6 is stopped (S2), when such pre-heating operation is started, the compressor 6 is stopped the (S2: YES), the temperature _{T C} is determined whether lower than the lower limit temperature _{T CL} (S3).

At this time, if T _C ≦ T _CL is not satisfied, that is, if the temperature T _C is not lower than the lower limit temperature T _CL (S3: NO), the air conditioner 1 proceeds to Step S1 and moves to the temperature T Repeat acquisition of _C. This, for example, when the outside air temperature is relatively high when the temperature T _C at time t1 is higher than the lower limit temperature T _CL is also envisaged, in such a case, because it is not necessary to perform the preheating operation. In step S3, when the compressor 6 is stopped by heating as described later, it is determined whether or not the compressor 6 is sufficiently cooled.

On the other hand, if T _C ≦ T _CL (S3: YES), the air conditioner 1 starts the operation of the compressor 6 (S4). At this time, the air conditioner 1 starts the operation of the compressor 6 by setting the operation frequency R to the upper limit frequency _RH .

  Subsequently, the air conditioner 1 determines whether the keep time has elapsed (S5). Here, the keep time is a time provided for maintaining the frequency for a certain time after changing the operating frequency R, and determining whether to change the operating frequency R and then change it. This corresponds to the period until That is, the air conditioner 1 of the present embodiment controls the operating frequency R to change stepwise by providing a keep time.

When it is determined that the keep time has not elapsed (S5: NO), the air conditioner 1 determines whether T _C ≧ T _CH2 , that is, whether the temperature T _C is equal to or higher than the allowable upper limit temperature T _CH2. Is determined (S6), and if T _C ≧ T _CH2 is not satisfied (S6: NO), it is determined whether a heating start signal is received (S9). The heating operation start signal is a signal received when the heating start time comes and when the user instructs the start of the heating operation.

Air conditioner 1, when not receiving a heating start signal (S9: NO), obtains the temperature T _C proceeds to step S1, and repeats the process described above. On the other hand, when the air conditioner 1 receives the heating start signal in step S9 (S9: YES), the air conditioner 1 executes the rapid heating operation process (S10) and starts the rapid heating operation. The rapid heating operation is an operation state basically similar to a well-known heating process in which the blower of the indoor unit 3 is operated to blow a predetermined warm air into the room, and thus detailed description thereof is omitted.

Thus, the air conditioner 1 in the period until the keep time elapses, the temperature T _C of the refrigeration cycle 18 continuously acquires, if the temperature of the refrigeration cycle 18 is not excessively high or low The determination and the rapid heating operation start determination are repeated.

When the keep time has elapsed (S5: YES), the air conditioner 1 executes the compressor frequency process shown in FIG. 4 (S8). Hereinafter, the compressor frequency processing, in order to simplify the description, with reference to the time variations of the temperature T _C of FIG. 5.

In the compressor frequency processing, as shown in FIG. 4, the air conditioner 1 first determines whether or not T _C ≧ T _CH1, that is, whether or not the temperature T _C is _{equal to} or higher than the upper limit temperature T _CH1 ( S11). For example, as shown in FIG. 5, the preheating operation processing at time t1 is started, a result of the operation by setting the compressor 6 to the upper limit frequency R _H, the temperature T _C gradually rises, T _C ≧ T at time t2 _Suppose that it becomes _CH1 .

In this case, in the compressor frequency processing shown in FIG. 4, the air conditioner 1 determines the time t2 (more precisely, when it is determined that the keep time has passed for the first time after the time t2 when T _C ≧ T _CH1 ). Since T _C ≧ T _CH1 (S11: YES), the flag is turned ON (S12). This flag is a flag provided to determine whether to lower or raise the operating frequency R. The air conditioner 1 reduces the operating frequency R when the flag is ON, and when the flag is OFF. Controls to increase the operating frequency R.

For this reason, when the flag is ON (S13: YES), the air conditioner 1 reduces the compressor frequency Down, that is, reduces the operating frequency R of the compressor 6 (S14). At this time, the air conditioner 1 reduces the operating frequency R by one step. Specifically, in the present embodiment, only one stage out of dividing the operating frequency range with the upper limit frequency _RH as the upper limit and the lower limit frequency _RL as the lower limit into a plurality of stages (four stages in the present embodiment), The operating frequency R is lowered. Thereafter, the air conditioner 1 returns to the preheating operation process shown in FIG. 3 and waits for the keep time to elapse.

Now, it elapsed keeping time at time t3 shown in FIG. 5, the temperature _{T C} at this time t3 less than the upper limit temperature _{T CH1,} and, and was lower limit temperature _{T CL} more. In this case, since the air conditioner 1 does not _satisfy T _C ≧ T _CH1 in the compressor frequency processing (S11: NO), the air conditioner 1 further determines whether T _C ≦ T _CL (S15), and T _C ≦ since neither T _CL (S15: nO), determines a flag (S13). Since the air conditioner 1 has the flag turned on at time t2 as described above (S13: YES), the operating frequency R of the compressor 6 is further lowered by one step (S14), and the process returns to the preheating operation process. To do.

Similarly, elapsed following keeping time at time t4 shown in FIG. 5, the temperature T _C is lower than the upper limit temperature T _CH1 in the time t4, and, in the case were the lower limit temperature T _CL above, the air conditioner 1 Since the flag is ON (S13: YES), the operation frequency R of the compressor 6 is further lowered by one step (S14), and then the process returns to the preheating operation process.

As described above, the air conditioner 1 performs control to continuously decrease the operation frequency R of the compressor 6 in a stepwise manner when the flag is ON.
Now, if you keep lowering the operating frequency R of the compressor 6, to keep down even if the temperature T _C of the refrigeration cycle 18, for example, as shown in FIG. 5, the temperature T _C is to lower than the lower limit temperature T _CL at time t5.

In this case, in the compressor frequency processing shown in FIG. 4, the air conditioner 1 satisfies T _C ≦ T _CL at time t5 (more precisely, when it is determined that the first keep time has elapsed after time t5). Therefore (S11: NO and S15: YES), the flag is turned off (S16), and since the flag is off (S13: NO), the compressor frequency Up, that is, the operating frequency R is increased by one level ( S17), the process returns to the preheating operation process.

Similarly, after that, when the flag is OFF, the air conditioner 1 increases the operation frequency R step by step until T _C ≧ T _CH1 . Note that when T _C ≧ T _{CH1 as} a result of increasing the operating frequency R, the flag is turned on and the operating frequency R is lowered stepwise as described above.

Thus, the air conditioner 1, by stepwise increasing or decreasing between the operating frequency R of the compressor 6 of the upper limit frequency R _H and the lower limit frequency R _L, the temperature T _C is the upper limit temperature T of the refrigeration cycle 18 It is controlled so as to remain between the _CH1 and the lower limit temperature T _CL.

Thus, in the air conditioner 1 of this embodiment, the vicinity of time t0, i.e., in the vicinity of the heating starting time, the temperature T _C of the refrigeration cycle 18 has become to a temperature suitable for rapid heating operation and the compressor 6 Is continuously operated, the time for restarting the compressor 6 is not required, so that the warm air can be blown immediately.

Incidentally, although the case where the temperature T _C exceeds the upper limit temperature T _CH1 is gradually lowered operating frequency R as described above, the influence of the outside air temperature, even by lowering the operating frequency R, also the operating frequency R even if the lower limit frequency R _L, the temperature T _C of the refrigeration cycle 18 is also envisioned that not fall. When the temperature T _C of the refrigeration cycle 18 continues to rise, or the refrigeration cycle 18 becomes overheated, it may be or become a high pressure state.

Therefore, in the present embodiment, the temperature to the maximum limit for the refrigeration cycle 18 during the preheating operation has set a permissible upper limit temperature T _CH2, the temperature T _C exceeds this allowable upper limit temperature T _CH2 is It is determined that the refrigeration cycle 18 is in an overheated operation state.

For example, as shown in FIG. 6, to start the preheating operation at time t11, the despite the operating frequency R since it exceeds the upper limit temperature T _CH1 went stepped down at time t12, the temperature T _C is It is assumed that the allowable upper limit temperature T _CH2 (the upper limit temperature allowed during the preheating operation) is reached at time t13.

In this case, since the air conditioner 1, since the temperature _{T C} has reached the allowable upper limit temperature _{T CH2,} i.e., a _{T C} ≧ _{T CH2} in the preheating operation process shown in FIG. 3 (S6: YES), The operation of the compressor 6 is stopped (S7). The air conditioner 1 acquires the temperature _{T C} (S1), since the compressor 6 is stopped (S2: YES) and determines whether the _{T C ≦ T CL (S3)} , T C is If it exceeds _TCL (S3: NO), the process proceeds to step S1 and the same determination is repeated.

That is, the air conditioner 1, when the temperature _{T C} of the refrigeration cycle 18 becomes the allowable upper limit temperature _{T CH2} or until the temperature _{T C} is below the lower limit temperature _{T CL,} in other words, the refrigeration cycle 18 is sufficiently The operation of the compressor 6 is stopped until it cools.

In this case, for example, as shown in FIG. 6, the temperature _{T C} is to lower than the lower limit temperature _{T CL} at time t14. In this case, the air conditioner 1, in the preheating operation process shown in FIG. 3, (S1 from the temperature T _C obtained a state in which the compressor 6 is stopped is below the lower limit temperature T _CL, S2: YES, And S3: YES), the operation of the compressor 6 is started (S4), and thereafter, the compressor frequency process is executed every time the keep time elapses as described above (S8), whereby the temperature T of the refrigeration cycle 18 is obtained. Control is performed so that _C falls within the range of the upper limit temperature T _CH1 and the lower limit temperature T _CL .

According to the embodiment described above, the following effects can be obtained.
The air conditioner 1 of the embodiment includes a refrigeration cycle 18, the indoor temperature sensor 16 for detecting the temperature T _C of the refrigeration cycle 18 (temperature detecting means), a refrigeration cycle 18 based on the temperature detected by the indoor temperature sensor 16 An outdoor control unit 14 (control means) for controlling the operation frequency R of the compressor 6 in the preheating operation for driving the refrigeration cycle 18 before the heating start time set by the user. it sets the operating frequency range defined by the predetermined upper limit frequency R _H and the lower limit frequency R _L Te is defined by the predetermined upper limit temperature T _CH1 and the lower limit temperature T _CL with respect to the temperature T _C of the refrigeration cycle 18 set the operating temperature range that, during the preheating operation, continued operation of the compressor 6, compressor so that the temperature T _C of the refrigeration cycle 18 is within the operating temperature range The operating frequency R of the motor 6 is changed within the operating frequency range.

  Thereby, since the compressor 6 is continuously operated during the preheating operation, it is basically unnecessary to restart the operation of the compressor 6. As a result, it becomes possible to blow out the warm air at a predetermined temperature, that is, the temperature in the operating temperature range at the heating start time, and the start-up time until the warm air at the predetermined temperature is blown out after the heating start time is reached. It can be prevented from increasing. That is, the rapid heating operation can be performed according to the name.

  Further, since the compressor 6 is continuously operated during the preheating operation, the temperature of the refrigeration cycle 18, particularly the indoor heat exchanger 15 can be maintained at a desired temperature, and at a time set by the user. When starting the heating operation, warm air at a set temperature can be blown out. That is, desired performance can be exhibited, for example, a feeling of heating intended by the user can be obtained.

  In addition, the air conditioner 1 can suppress a high temperature and a high pressure by performing the preheating operation process, that is, by adjusting the temperature of the refrigeration cycle 18 with the operation frequency R of the compressor 6.

The air conditioner 1 can execute a rapid heating operation in which warm air can be blown into the room in a shorter time than a normal heating operation, and a temperature range set in advance for the rapid heating operation can be refrigerated. It is set as the operating temperature range to be set for the temperature T _C of the cycle 18. Thereby, the warm air of the temperature as intended by the designer can be supplied promptly at the start of the rapid heating operation, and a comfortable heating environment can be provided to the user.

Air conditioner 1, when it reaches the allowable upper limit temperature T _CH2 is set higher than the upper limit temperature T _CH1 temperature T _C of the operating temperature range of the refrigeration cycle 18, preheating operation to stop the operation of the compressor 6 Is temporarily stopped. Thereby, while preventing abnormal overheating etc., the time of preheating operation can be shortened.

If you stop the operation of the compressor 6, the air conditioner 1, the temperature T _C of the refrigeration cycle 18 is lowered to the lower limit temperature T _CL, resumes preheating operation. In such a case, since the room temperature and the outside air temperature are relatively high, even if the preheating operation is stopped halfway and the preheating operation is restarted again, the rapid heating operation is promptly performed for the user at the heating start time. It can be done in a comfortable state.

  The air conditioner 1 is provided with a heat storage unit 12 having a heat storage material that stores heat discharged by the compressor 6 during operation on the outer periphery of the compressor 6. Thereby, when starting the operation of the compressor 6, the operating frequency R of the compressor 6 can be suppressed to be lower than that when the heat storage unit 12 is not provided by dissipating heat from the heat storage unit 12. Therefore, power consumption can be reduced.

  In the embodiment, one hour is set as the predetermined time, but the present invention is not limited to this, and may be set as appropriate according to, for example, the operating capability of the compressor 6. Further, a predetermined time may be set each time according to the room temperature or the outside air temperature.

In the embodiment, it is determined whether to increase or decrease the operating frequency R based on the actual temperature value (temperature T _C ) acquired during the keep time. However, the determination is made based on the temperature change amount during the keep time. May be. For example, a tendency acquisition means for acquiring a tendency of temperature change is provided, and when the temperature rises and it is predicted that it will exceed the allowable upper limit temperature T _CH2 from the amount of the rise, the compressor 6 does not wait for the keep time to elapse. It is conceivable to stop the operation and temporarily stop the preheating operation. As a result, when the room temperature or the outside air temperature is relatively high, the preheating operation time can be shortened and the compressor 6 can be prevented from entering the overheat operation state.

(Second Embodiment)
Hereinafter, the second embodiment will be described with reference to FIGS. 7 and 8. In the second embodiment, the contents of the compressor frequency processing are different from those in the first embodiment. The contents of the preheating operation process are the same as those in the first embodiment, and will be described with reference to FIG.

In this embodiment, the air conditioner 1, when performing the preheating operation, first, the target temperature T _CM is a target value of the temperature T _C of the refrigeration cycle 18, as shown in FIG. 7, than the allowable upper limit temperature T _CH2 and sets in advance a lower range, set a predetermined tolerance α with respect to the target temperature T _CM. In this embodiment, the tolerance α is set to a relatively low value such as 0.5 ° C. in order to accelerate the temperature convergence. The range of this target temperature T _CM ± α corresponds to the target temperature zone. Further, the target temperature T _CM + α corresponds to the upper limit temperature, and the target temperature T _CM −α corresponds to the lower limit temperature.

Hereinafter, the flow of the compressor frequency processing (see FIG. 8) according to the present embodiment will be described with reference to FIG. 7, but the air conditioner 1 according to the present embodiment has a temperature of the refrigeration cycle 18 during the preheating operation. T _C is performing control so as to converge to the target temperature range of the target temperature T _CM ± α.

Specifically, as shown in FIG. 7, the air conditioner 1 starts the preheating operation at time t21, which is a predetermined time before, when the time t20 is set to the time at which the rapid heating operation is started. At this time, the air conditioner 1, as in the first embodiment executes the preheating operation process shown in FIG. 3, starts the operation of the compressor 6 at the upper limit frequency R _H, acquisition and keeping time of the temperature T _C Repeat the determination of whether it has passed.

And if the air conditioner 1 determines with the keep time having passed (S5: YES), it will perform the compressor frequency process shown in FIG. In this compressor frequency process, the air conditioner 1 first determines whether the temperature _{T C} of the refrigeration cycle 18 is the target temperature _{T CM} + alpha or (S21). For example, when the temperature _{T C} of the refrigeration cycle 18 as the time t21 is lower than the target temperature _{T CM} + alpha, the air conditioner 1, _{T C} ≧ _{T CM} + _α at since not (S21: NO), followed by determines whether the temperature _{T C} is below the target temperature _{T CM -α} (S23).

For the time t21, since the temperature _{T C} is lower than the target temperature _{T CM-.alpha.,} the air conditioner 1, _{T C} ≦ _T since _CM is -α (S23: YES), compressor frequency Up, i.e., the compressor 6 is performed to increase the operation frequency R by one step (S24). However, since the operating frequency R is the upper limit frequency _RH at the start of the preheating operation, the operating frequency R is not substantially changed at this time. Thereafter, the air conditioner 1 returns to the preheating operation process.

Now, the temperature T _C reaches the target temperature T _CM-.alpha. at time t22 preheating operation is continued. In this case, since the air conditioner 1 is not T _C ≧ T _CM + α (S21: NO) and is not T _C ≦ T _CM -α (S23: NO), the compressor frequency keeps, that is, the current The operation frequency R of the compressor 6 is maintained (S25), and the process returns to the preheating operation process.

Thereafter, the temperature T _C is to have reached the target temperature T _{CM +} alpha at time t23 is continued further preheating operation. In this case, since the air conditioner 1 satisfies T _C ≧ T _CM + α (S21: YES), the compressor frequency Down, that is, the operating frequency R of the compressor 6 is lowered by one step (S22), and then the preheating operation processing is performed. Return to

Thus, the air conditioner 1 of this embodiment, the allowable temperature T _C of the refrigeration cycle 18 when adjusted by changing the operating frequency R of the compressor 6, and the target temperature T _CM, its target temperature T _CM set the tolerance alpha is, when the temperature Tc is above the T _{CM +} alpha lowers the operating frequency R, when the temperature T _C is below the T _CM-.alpha. increases the operating frequency R, temperature when the T _C is in the range of the target temperature _{T CM} ± alpha, that _is, when the range of _{T CM + α>Tc> T} CM -α controls to keep the operating frequency R constant.

  As a result, the temperature Tc converges to the target temperature range, and the rapid heating operation can be started at an arbitrary blowing temperature. Therefore, it is possible to obtain the same effects as those of the first embodiment, such as being able to blow out warm air at a predetermined temperature in a short time when the heating start time is reached.

Further, in this embodiment, the temperature T _C of the refrigeration cycle 18 is converged to the target temperature zone that is configured as a relatively narrow temperature range, at the start of the quick heating operation, warm air in a more comfortable temperature Can be provided.

(Other embodiments)
The numerical values and the like shown in each embodiment are examples and are not limited thereto.
In the first embodiment, an example in which the temperature when the compressor 6 is stopped and restarted is set to the lower limit temperature T _CL is shown. However, for example, the lower limit temperature T _{CL is changed} to the upper limit temperature T _CH1 based on the operation capability of the compressor 6. When the operation restart temperature T _R (where T _CL <T _R <T _CH1 ) is set within the range up to and the temperature T _C falls below the operation restart temperature T _R , in other words, the temperature T _C is the lower limit. The operation of the compressor 6 may be resumed at a time before the temperature _TCL falls below. Temperature T _C is assumed to be a slight time lag from below the lower limit temperature T _CL to a temperature T _C and restarting the operation of the compressor 6 is higher than the lower limit temperature T _CL, the start of rapid heating operation during the time lag there is instructed, it may impair the comfort of the user from the temperature T _C is outside the temperature range suitable for the quick heating operation, by setting the restarting operation temperature T _R, the comfort of the user Can be avoided.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

  In the drawings, 1 is an air conditioner, 6 is a compressor, 7 is an outdoor heat exchanger (evaporator during heating operation), 8 is a decompressor, 9 is a four-way valve, 11 is an accumulator, 12 is a heat storage unit, and 14 is an outdoor unit. Control unit (control means), 15 is an indoor heat exchanger (condenser during heating operation), 16 is an indoor temperature sensor (temperature detection means), and 18 is a refrigeration cycle.

Claims (5)

A refrigeration cycle having a compressor, an accumulator, a condenser, a decompressor, an evaporator, and a four-way valve, wherein the cooling operation and the heating operation are switched by the four-way valve;
Temperature detecting means for detecting the temperature of the refrigeration cycle;
Control means for controlling the refrigeration cycle based on the temperature detected by the temperature detection means,
In the preheating operation for driving the refrigeration cycle before the heating start time set by the user, the control means has an operation frequency range defined by a predetermined upper limit frequency and a lower limit frequency with respect to the operation frequency of the compressor. And setting an operating temperature range defined by a predetermined upper limit temperature and a lower limit temperature with respect to the temperature of the refrigeration cycle, and during the preheating operation, while continuing the operation of the compressor, An air conditioner characterized in that the operating frequency of the compressor is changed within the specified operating frequency range so that the temperature falls within the operating temperature range.   The control means sets a target temperature range defined by a target temperature that is a target value of the temperature of the refrigeration cycle during the preheating operation and a tolerance allowed for the target temperature, and the temperature of the refrigeration cycle is When the temperature is higher than the target temperature range, the operation frequency of the compressor is decreased, and when the temperature of the refrigeration cycle is lower than the target temperature range, the operation frequency of the compressor is increased, and the temperature of the refrigeration cycle is the target temperature. When in the temperature range, the operating frequency of the compressor is maintained, and when the operating frequency is changed, the operating frequency after the change is maintained for a predetermined keeping time, thereby setting the temperature of the refrigeration cycle to the target. The air conditioner according to claim 1, wherein the air conditioner is converged in a temperature zone.   When the temperature of the refrigeration cycle reaches an allowable upper limit temperature set higher than the upper limit temperature of the specified operating temperature range, the control means stops the compressor operation and temporarily stops the preheating operation. The air conditioner according to claim 1 or 2, characterized in that the time for the preheating operation is shortened.   The air conditioner according to any one of claims 1 to 3, further comprising a heat storage unit that is provided on an outer peripheral portion of the compressor and serves as a heat storage material that stores heat discharged by the compressor during operation.   The control means is capable of executing a rapid heating operation in which warm air can be blown into the room in a shorter time than a normal heating operation, and a temperature range preset for the rapid heating operation is set in the freezing The air conditioner according to any one of claims 1 to 4, wherein the air conditioner is set as an operating temperature range set with respect to a cycle temperature.

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